The invention relates to an antenna, and more particularly to a wideband antenna receiving wireless video signals.
FIG. 1a shows a conventional inverted F-shaped flat antenna 10, which comprises a ground element 1, a conductive element 2, a receiving element 3, a short element 4 and a signal line 5. The receiving element 3 is connected to an end of the conductive element 2 and is perpendicular thereto. The signal line 5 is connected to another end of the conductive element 2. The ground element 1 is grounded. The short element 4 is connected to the receiving element 3 and the ground element 1 to minimize the antenna 10.
FIG. 1b shows signal reception of the antenna 10. When a center frequency of the signals received by the antenna 10 is 425 MHz, the bandwidth (bandwidth defined as signals having gain lower than −10 dB) thereof is less than 25 MHz.
Improvement in digital television technology has lead to a demand for receiving television signals in different frequencies to provide different television channels by flat antenna. The frequencies of wireless digital television signals are between 400-800 MHz, and an antenna for receiving wireless digital television signals must have a bandwidth of at least 200 MHz. Thus, a conventional flat antenna cannot be utilized for receiving wireless digital television signals.